1. Field of the Invention
The present invention relates to LED lighting assemblies, especially to LED lighting assemblies capable of replacing fluorescent tubes.
2. Description of the Related Art
Lighting is important to our daily life, and after Edison invented the light bulb, we have been using lighting assemblies day and night. Current lighting assemblies mainly include incandescent light bulbs, fluorescent tubes, and compact fluorescent lamps. Compact fluorescent lamps are used to replace incandescent light bulbs to provide compatible luminance in same operation manner. Fluorescent tubes are popularly used in offices or public places of large area.
For the present, environmental protection issues of power saving, low carbon consumption, and products without mercury are highly concerned, and LEDs (light emitting diodes) happen to meet the mentioned requirements. Besides, as LEDs are solid state devices, unlike traditional fluorescent tubes made of fragile glass, therefore they are far more convenient for transportation than traditional fluorescent tubes. In addition, LEDs have the advantages of small size and directional lighting, so they are suitable to be applied in lighting applications requiring small size or directional lighting, and are therefore becoming the main choice of next generation lighting in replacing traditional fluorescent tubes.
Please refer to FIG. 1, which illustrates a cross sectional view of a prior art LED lighting assembly. As illustrated in FIG. 1, multiple LEDs 20 are mounted inside a housing 10 of a rectangular shape, and a light output face of the housing 10 is shielded by a lampshade 16. For the present, most LED lighting assemblies are designed in this way.
However, as the cross section of a lamp tube is of a curved shape, therefore some LED lighting assemblies are designed to be of tube type instead. Please refer to FIG. 2, which illustrates a cross sectional view of a prior art tube type LED lighting assembly. As illustrated in FIG. 2, multiple LEDs 20 are mounted inside a housing 12 of a half-tube shape, a transparent lampshade 18 of a half-tube shape connects with the housing 12 to form a lamp tube, and usually, a plate, as can be seen in the figure, is used in the housing 12 to mount the LEDs 20.
Although the small size of LEDs have the advantage of being capable of reducing the thickness of a lighting apparatus, however, the small size can also make the light intensity in a unit area so high as to result in a dazzling effect. To reduce the dazzling effect, one solution is to utilize a frosted lampshade to diffuse the light rays emitted from each LED. However, the intensity of output light will be attenuated accordingly. Besides, the light emitting efficiency of LEDs has been increasing per year as the manufacturing process keeps improving, and the increased light intensity has added challenges to the diffusion effect of the frosted lampshade. Under this circumstance, the frosted lampshade has to increase scattering effect to make the output light uniform, but this will further sacrifice the intensity of the output light.
In view of the mentioned problems, the present invention proposes a design to provide a superior LED lighting assembly, which is capable of reducing dazzling effect by using a lightly frosted lampshade, or even using no lampshade.